Police say 40-year-old Scott Mitchell of Sebastopol, Calif., was arrested on suspicion of driving under the influence, failure to obey a stop sign and driving on train tracks.

"It appears he just drove into the tunnel and his vehicle got stuck when it hit a concrete step," Officer Albie Esparza told The Associated Press. "We believe he was under the influence of alcohol. It's very fortunate that nobody was injured."

San Francisco P.D. via AP

Scott Mitchell, 40, of Sebastapol, Calif., was arrested on suspicion of driving under the influence over allegations he shut down San Francisco's subway system for more than two hours after driving his SUV onto the underground tracks, police said.

No trains were involved, police said.

Witnesses said the driver was traveling about 40 mph when he drove into the the tunnel.